Polishing tool



g- 1932- D. R. JOHNSTON POLISHING TOOL Filed March 10, 1930 2 Sheets-Sheet l 1 1932- D. R. JOHNSTON POLISHING TOOL Filed March 10, 19 30 2 Shegts-Sheet flu/MM Patented Aug. 2, 1932 UNITED STATES.

Davin a. mansion, or nn rnoi'r, MICHI AN POLISHING T001.

Application filed March 10, 1930. Serial No. 484,687.

This invention relates to the art of preparing and finishing surfaces and more particularly to improvements in power operated hand tools for surface working.

While not limited in its application and use it may be said that the invention has been particularly designed for use in automobile body building plants where the work must not only be of high quality but must be turned out with care and at a rapid rate. Heretofore it has been the universal custom and practice among body builders to sand and polish their product by hand, princi-.

pally for the reason that mechanical expedients available, due partly to the character of the work, have failed to attain the perfection of hand work.

To provide a power device which will to an extent simulate hand work and reduce the 2 labor and skill necessary in hand work and the time interval to complete a given job with equal and even better results, is one of the primary objects of the present invention.

It is a further object of the invention to provide a device which will be useful not only on smooth surfaces but also on curved surfaces and in and around sharp corners without danger of scratching or otherwise marring the work.

Another object of the invention is to provide an improved finishing device whose working face consists of a series of individual parts or flaps which when in use lay down over one another and afford a continuous succession of wiping or cutting edges and which flaps are detachably mounted on a carrier or support for replacement from time to time after they wear and their period of usefulness ends.

Various other objects of this invention and its sundry features or advantages will appear from the following specification which refers to the accompanying drawings, wherein Figure 1 is a perspective view of the tool being used on the surface of an automobile bod Figure 2 also shows the tool as it would appear in use, but in a diiferent relation.

Figure 3 is an elevation of the working rotary carrier face of the finishing device with parts thereof broken away. 1

Figure 4 is a side elevation partly in section of the parts shown in Figure 3.

Figure 5 is an elevational view illustrat- 5b ing slight modifications.

Figure 6 is a side elevation of the parts shown in Figure 5', and Figure 7 is a detail view of one of the finishing flaps.

Referring to the drawings, 1 indicates an enclosed body for an automobile having a side window 2 and a rear window 3. In Figure 1 the tool is shown in the hand of an operator in contact with a curved portion of the body between the rear and side panels. 05 It involves a series of flexible finishing flaps 4 shown as being replaceably mounted on a.

5. Operating mechanism for the carrier is enclosed within a housing 6 having a handle 7, and a flexible conduit or sheath 8, and may comprise a flexible power transmitting cable 9, leading from some suitable source of power, as for example, an electric motor preferably positioned overhead, and connected with the beveled gear 10 having a bearing in the housing 6 and meshing with the beveled gear 11 on a drive shaft 12.

A flat headed nut 13 screw threaded on the end of the shaft 12 serves to removably secure the carrier on the driving shaft. In use, particularly where the automobile bodies are moved in quick succession along an assembly line on a continuous conveyor, it will be found desirable to employ two of the finishing devices, one for each side of the body, a workman being provided to handle each tool.

The rotatable carrier 5 may comprise merely a disc of suitable material. It is preferably of a material such as soft sppnge rubber or the like, so thatthere will e no likelihood of any hard sharp edges being brought into contact with the work. Sponge rubber or its equivalents when used alone may, however, be found too pliable and to avoid this objection, it is proposed to provide a stiffening or backing plate of slightly smaller diameter than the soft rubber so that the centralportion is stiff and reinforced while. the peripheral edge is left soft and suitable abrasive material.

resilient. The soft flexible disc is indicated at 14 in the drawings and the backing plate at 15. This backing plate may be of heav canvas, hard rubber or the like, and is pre erably vulcanized or bonded to the rear face of the disc 14. A single disc of rubber so formed that'it is relatively stiff thruout its central portion and pliable at its periphery could also be employed as a carrier as will be obvious.

- When' the surface is to be cleaned and smoothed preparatory to applying a. coat of paint or the like, the flaps 4; may consist of For polishing and iving to a coated surface a high luster the aps are then made of material suitable for polishing. -A material found most desirable for polishin is a villous fabric or one having a short c ose nap of erect threads that afford a thick soft pile, velour being an example. Velours are used quite extensively in automobile upholstering work and this invention affords an opportunity for the automobile builder to salvage and use up scraps left from the upholstering operations. The short-threads are found to be quite live and they quickly and readily recover from deformation, and for this reason the dirt and grit that is picked up and formed upon their movement over the surface being polished, will not readily pack or cake hard on the flaps, but there will be a tendency to throw off such collections. Other materials that allow the dirt to adhere thereto quickly become soaked or caked and then scratch and mar the finish and soon have to be discarded.

The finishing flaps, whether they be of abrasive material or of soft polishing fabric, are preferably detachably fixed to the carrier in order thatathey may be replaced from time to time. To afford a quick detachable connection it is proposed to provide the carrier with alseries of radial slits, formed through hot ,the soft disc 14 and the backing plate 15. Each flap may be cut or formed to the shape illustrated in Figure 7, where 16 indicates the body portion or work contacting portion of the flap, 17 a narrow neck tobe inserted in a slit, and of substantially the size of the slit, and 18 an enlarged head to secure the flap in place and prevent it being pulled out of the slit. The slit can be readily expanded with a suitable tool and the flap flexed sufficiently to permit attachment of the parts. When the series of flaps are assembled on the carrier, the body portion 16 will extend from the face of the disc 5 until such time as the disc is rotated and the flaps are brought into contact with the surface. The flaps will then flatten out and lay down over one another in partially overlapped relation as is clearly illustrated in the drawings. The marginal portion along the edge 20 of the flap will project beyond the periphery of the carrier 5 and protect the of contact with the work surface as the disk or carrier rotates, it being understood that in normal operation, the tool will be held in a plane inclined to that ofthe surface to be worked somewhat after the fashion illustrated in Figure 2. It will be seen that as the flaps are moved into contact with the work they are pressed together while they have a tendency to recover and spread apart after leaving the surface. This movement of the flaps relative to and over each other serves in a measure to agitate any dirt picked up and keep it from. packing hard and in a condition to be thrown off or dusted out.

Figure 2 also clearly illustrates that the tool is adaptable for and can be easily used in close quarters and in and around moulding beads of the automobile. The tool reaches all of the surface and its flexible edge yields to prevent digging or scratching the surface. The several individual flaps laid down on the work in succession closely simulates hand rubbing and polishing without requiring the expenditure of any effort on the part of the operator other than is necessary to press the tool against and move it over the work.

Either a flap formed of a single thickness, as illustrated in Figure 3, or a flap of double thickness, as indicated in Figure 5, may be employed. In the latter case, the flap is simply cut to size and then folded back upon itself to afford a working face on both sides of the flap.

While the above description has been more or less specific, it will be understood that the invention is not limited to exact details referred to and that the parts and their arrangement can be variously modified within the scope of appended claims.

I claim:

1. A rotary finishing device, including a rotary disc having a relatively stiff center portion and a soft flexible edge portion and being provided witha series of slits therein, and a series of renewable flaps removably carried by the disc with portions thereof projecting through the slits in interlocking relation therewith and provided each with a finishing surface for intermittent contact with the work as the disc is rotated.

2. Means operable to impart a surface finish, including a rotatable carrier having a series of slits therein, and a series of surface finishin flaps having restricted necks for passage t ru the slits to secure the flaps to the carrier, said flaps being adapted to overlap each other to succession of wiping e ges.

resent a continuous 3. Means operable to impart a surface finish, including a rotary disc of soft flexible material provided with a series of slits, and a plurality of flexible work wiping flaps projecting laterally from the face of the disc and beyond the peripheral edge thereof with portions projecting through saidslits for detachable connection with the disc.

4. Means operable to impart a surface finish, including a rotary disc of soft flexible material, and a plurality of flexible work wiping flaps projecting laterally from the face of the disc and beyond the peripheral edge thereof, and reinforcing means to stiflen a portion of the disc.

5. Means operable to impart a surface finish, including arotary disc of relatively 1 soft flexible material, a bacln'ng plate of stiffer material and of smaller size than the disc, bonded to the back thereof, and a series of flexible work wiping flaps projecting from the front of the disc.

6. In a surface finishing tool, a rotary disc having a soft peripheral edge and a plurality of overlapping work-Wiping flaps carried by the disc on one face thereof.

7. In a surface finishing tool, a plurality of work wiping flaps, and a rotatable carrier therefor, including a soft rubber disc and a hard rubber backing plate.

8. Structure 'of claim 7, wherein the disc projects beyond the periphery of the plate to aflord a soft marginal portion to the carrier.

9. In a surface finishing tool, a disc of comparatively soft rubber, a plate of comparatively hard rubber bonded to the back of the disc and having its peripheral edge spaced inwardly from the periphery of the disc, the plate and disc having series of alined radial slits to removably receive parts of and retain finishing material onthe face of the disc.

10. In a surface finishing device, a working flap comprisinga body portion for contact with the work, a neck portion for projection thru a slit in a movable carrier, and an enlarged head to hold the neck in its slit.

11. In a surface finishing tool, a rotatable 5o carrier comprising a disc of comparatively soft rubber, and a stiffening plate therefor of hard rubber bonded to the back of the disc, and having a series of radial slits therein, a series of flexible finish flaps, each comprising a body for contact with the work, a neck for removable projection thru a slit in the carrier, and a head to retain the neck in place, said body portions being adapted to lay down in overlapping relation on the face of the carrier and to project beyond the soft edge thereof, to present a continuous succession'of work contacting wiping edges.

In testimony whereof I aflix my signature.

DAVID R. JOHNSTON. 

